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Sierra's new data and my results, not even close?

I just got my new Sierra load data book and was making loads for my 22-250 for testing with the 69gr bullet and Reloader 16 at the listed 2.350 which gives me a .008 jump in my Shilen 8T 26 inch barrel. Sierra has a max load of 37.5gr and a listed velocity of 3400 this is also their "accuracy" load. Well my barrel is longer than their listed barrel so I reduced this load slightly hoping to get around that 3400fps. My load at 36.9gr only posted a 2844fps? This did not even make their slowest loading? Not sure how this can be, they cant be that far off??
 
As B23 said it could be your chronograph.....

Also you don’t know all the variables involved. Sierra most likely used a SAAMI min spec test barrel. So this means a 24” finish length, SAAMI min spec chamber and min spec on the bore and groove for rifling which would be .2190” on the bore +.0005” for tolerance and .2240” for the groove size +.0005” for tolerance. SAAMI spec on twist is 1-12 but twist doesn’t have an effect on pressure that much and your barrel being +2” long if anything should’ve given you a little extra velocity. So with that being said...

What chamber reamer was used in your rifles barrel? Got a chamber reamer print?
Do you know the bore and groove size to the .xxxx” decimal place?

With out knowing these other things....it could be the chronograph and or it could be the difference in your barrel vs. the spec test barrel that Sierra used and your only guessing.

Bullet makers like Sierra, Hornady etc...as well as ammo makers have to adhere to strict guide lines when doing testing and also they have to make sure when they do testing they also have to use reference ammo when setting up everything. Reference ammo is spec built ammo that you and I don’t have access to. Spec. Ammo when run thru a test barrel....the barrel and ammo has to give x amount of velocity and at x amount of pressure with minimal corrections. This way during testing they can make sure everything is giving them correct readings to make sure load development and data isn’t skewed at all.

Later, Frank
Bartlein Barrels
 
I just got my new Sierra load data book and was making loads for my 22-250 for testing with the 69gr bullet and Reloader 16 at the listed 2.350 which gives me a .008 jump in my Shilen 8T 26 inch barrel. Sierra has a max load of 37.5gr and a listed velocity of 3400 this is also their "accuracy" load. Well my barrel is longer than their listed barrel so I reduced this load slightly hoping to get around that 3400fps. My load at 36.9gr only posted a 2844fps? This did not even make their slowest loading? Not sure how this can be, they cant be that far off??


Double check your scale and make sure you’re not 5 grains low or something like that.

Or your chronograph is not working properly.
 
I don't have a chronograph I'm using a doppler radar unit (Labradar) and it works flawlessly every time. Same day running 6mm Creedmoor across it with Hornady's "match" ammo I was getting 2969fps against their advertised 2960 so that pretty dang close. I wouldn't think my scale would be off that much as 5 grains more would not even fit in the case. I'm getting ready to reload some 6mm Creedmoor using the RE-16 and match Hornady's load of 40.2 grains so we'll see if something is going on there.
I have come across data not jiving up before but never to this extreme. Mostly its just a hundred or so fps difference and many thing can make that happen but this was crazy slow for I should have got. I'll be waiting to see what fyrewall comes up with on his reloads with RE-16....
 
IMOP, there just aren't many possibilities as to what produces a recorded speed that much lower. If the radar is accurate, and the bullet is really going that slow, there can be only one cause. Low charge weight.

If you have some that were not shot, dump the charge and weigh it. Mistakes happen, i know I make my share of them.
 
Have you tried any of Sierra's listed loads for a different powder in your setup? If so, did it give you a velocity closer to the book value?

In general, there are a few things that could cause a difference between your actual velocity and the published value, such as case volume (i.e. brand of brass) and primer brisance. However, I wouldn't have expected a difference of almost 560 fps slower. It would probably be best to check every variable, one by one, to be sure everything was correct as a first step. Secondly, because your velocity was so much slower than expected, be very careful in what you try to increase it as you might run into pressure/safety issues.
 
I know mistakes do happen and yes the charges could have been light, I may retest again with that powder after my 6mm Creedmoor test later this week.
Ned Ludd, I have also tested IMR4451 powder with much better results. They list the 4451 max at 37.6gr with velocity at 3300, my test loads was 35.5gr at 3201 and 36.4 at 3282 much closer to what I see with the longer barrel.
 
I just got my new Sierra load data book and was making loads for my 22-250 for testing with the 69gr bullet and Reloader 16 at the listed 2.350 which gives me a .008 jump in my Shilen 8T 26 inch barrel. Sierra has a max load of 37.5gr and a listed velocity of 3400 this is also their "accuracy" load. Well my barrel is longer than their listed barrel so I reduced this load slightly hoping to get around that 3400fps. My load at 36.9gr only posted a 2844fps? This did not even make their slowest loading? Not sure how this can be, they cant be that far off??
Something does seem amiss. That's the velocity range of the 223 almost with that bullet.
 
I know mistakes do happen and yes the charges could have been light, I may retest again with that powder after my 6mm Creedmoor test later this week.
Ned Ludd, I have also tested IMR4451 powder with much better results. They list the 4451 max at 37.6gr with velocity at 3300, my test loads was 35.5gr at 3201 and 36.4 at 3282 much closer to what I see with the longer barrel.
Never saw any load data for RL16 and the 22-250. I thought the RL16 was fairly new but never saw anything for it with the 22-250. I'm not saying load data doesn't exist but make sure it's a powder that's compatible with that cartridge. I've seen RL15/17 but nothing in 16. Again being fairly new as far as I know, maybe there is data out there that I haven't seen. Too many other powders in my arsenal to consider leaving for another at this point
 
With R16 in a 243 and 70 gr bullet you need 45 gr to get 3500's. Alliant doesn't list any 22-250 loads with r16. Not sure how you can get to 3500 in a 22-250 with 37.5 gr, that's r15 load range.
 
Man I hope i'm not breaking a bunch of copyright laws here but this is a pic of the page right from Sierras new load data book. I just received this book like 4 days ago.

KIMG1059.JPG
 
Did Sierra have 37.5 grains of Re16 with a 69 grain bullet @ 3,400 fps and was this their accuracy load?

For years I have been using 35.0 grains of H4350 with 75's and 36.0 of H4350 with 68-69's.
Re16 seems to be a logical replacement for H4350 and H414.
Re16 is double base and might give higher velocities than H4350.
Re16 has a similar burn rate as H4350
Re16 is temp insensitive like H4350 and unlike H414 that reacts to big temperature changes (20*-90*)
35 & 35.5 grains of Re16 use about 98 % of my .22-.250 case capacity - COAL 2.661, 75 ELDM bullet.

The Alliant site has .22-.250 loads using Re15 with 55 grain bullets, 37.5 grains with 55's.
See my above pic right from the new book...
 
My thought is that if you've tried a load from the manual using a different powder (4451) and achieved a velocity within a few fps of the listed/expected velocity from the manual, that tells pretty clearly that something must be off with the Re16. That information doesn't allow you to state exactly what is wrong (i.e. incorrectly weighed charge, some problem with that Lot of powder itself, a typo or mistake for Re16 in the Sierra manual, etc.), but it suggests the problem is not your setup or reloading practices.
 
My thought is that if you've tried a load from the manual using a different powder (4451) and achieved a velocity within a few fps of the listed/expected velocity from the manual, that tells pretty clearly that something must be off with the Re16. That information doesn't allow you to state exactly what is wrong (i.e. incorrectly weighed charge, some problem with that Lot of powder itself, a typo or mistake for Re16 in the Sierra manual, etc.), but it suggests the problem is not your setup or reloading practices.
Not saying that I did not make a mistake, can prove it either way now? I'm going to wait till other data comes in or we'll see how my 6mm Creedmoor loads do. BTW the 6mmCM and the 22-250 have almost the same case size and the load I'm trying is 40.1gr of the RE-16 and that is not even max.
 
The new Sierra Re16 data appears to be right in line with that of H4350. Thanks for the verification - I will have more confidence in my Re16 load testing this Thursday, 35.0 & 35.5 grains with 75 ELDM bullets. H380 & PP2000MR loads appear but no H414 loads. I will make a screen shot of this page and will plan to buy a new Sierra manual.
In the past the H414 was my primary load with 35.2gr netting 3200fps with a magnum primer. This load would print under an inch at 300yds but looking for temp stability has me looking at other powders and H4350 was not it. When I got this new book and seen that RE-16 was their accuracy load I went out and bought a couple of pounds to play with.
 
Not saying that I did not make a mistake, can prove it either way now? I'm going to wait till other data comes in or we'll see how my 6mm Creedmoor loads do. BTW the 6mmCM and the 22-250 have almost the same case size and the load I'm trying is 40.1gr of the RE-16 and that is not even max.

Not saying you made a mistake, it's just one of the possible explanations for why your velocity with Re16 could be so much lower than expected. My point is that you've obtained the expected velocity in the same setup using a different powder. That strongly suggests that the explanation for the low velocity value specifically has something to do with the Re16, although the exact explanation is impossible to determine at this point with the available information. I suspect you'll be able to figure it out in time. The alternative is simply to use a different powder that gives you the velocity you're looking for at an appropriate charge weight. Of the alternatives, determining in a stepwise and systematic fashion why the velocity with Re16 is so low might involve the greater effort, but it might also be a more satisfying approach than taking the path of least resistance and using a different powder. Either way, good luck with it.
 

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